Remove hardcoded values from projets api test
What does this MR do?
This MR is follow up to !53036 (merged) that replaces hard coded ids values in test to avoid random test failures and make them aligned with https://docs.gitlab.com/ee/development/testing_guide/best_practices.html#general-guidelines
Use non_existing_record_id/non_existing_record_iid/non_existing_record_access_level when you need an ID/IID/access level that doesn’t actually exists. Using 123, 1234, or even 999 is brittle as these IDs could actually exist in the database in the context of a CI run.